CASE WHEN TIMESTAMPDIFF(MINUTE,o.createDate,o.chargingStartDate) != THEN 'APP解锁计费' ELSE '系统自动计费' END TIMESTAMPDIFF(MINUTE,o.createDate,o.chargingStartDate) o.chargingStartDate减去o.createDate相减后得到分钟,如果后者小于前者分钟为负数. SELECT TIMESTAMPDIFF(MONTH,'2009-10-01…